Muggy Mornings and Marginal Risks: San Antonio’s High-Humidity Thursday

A Warm and Humid Start for the Alamo City

San Antonio is waking up to a thick blanket of humidity and gray skies this Thursday, March 5, 2026. As the lead editor for sanantonio.news, I have been analyzing the latest data from the National Weather Service and regional meteorological models to provide a comprehensive look at what you can expect today. We are currently navigating a weather pattern defined by deep Pacific moisture funneling into South Texas, resulting in a day that is unseasonably warm and notably muggy.

Morning Forecast: Overcast and Misty

The morning hours have seen a mild start with temperatures hovering around 70°F. If you are heading out for an early commute or a walk along the River Walk, you will likely encounter patchy mist and drizzle. Humidity levels are currently peaking at a staggering 88%, making the air feel significantly heavier than the thermometer suggests. Expect overcast skies to dominate through at least 10:00 AM, with south-southeast winds moving at a steady 10 to 15 mph.

Afternoon Outlook: Rising Temperatures and the 'Storm Cap'

As we transition into the afternoon, the sun is expected to make a partial appearance. Forecasters are predicting a daytime high between 84°F and 87°F. Despite the sunshine, the UV index is rated at an 8 (Very High), so sun protection is highly recommended for anyone outdoors. Between 2:00 PM and 9:00 PM, San Antonio falls under a 'Marginal Risk' (Level 1) for isolated severe thunderstorms. Meteorologists are keeping a close eye on a 'capping inversion'—a layer of warm air aloft that often acts as a lid, preventing storms from firing up. If this cap breaks, the city could see scattered showers or isolated thunderstorms capable of producing small hail and wind gusts up to 25 mph.

Evening and Overnight: Cooling Down

Once the sun sets, the risk for severe weather will begin to diminish, though a 20% chance of light rain remains in the forecast. Temperatures will slowly retreat toward an overnight low of 69°F. While the immediate San Antonio area is not currently under any active wind or red flag warnings, neighboring regions to the west are facing high fire danger, so it is important to remain vigilant of any shifting conditions.

Looking Ahead

Today’s muggy conditions serve as a precursor to a more significant weather shift expected this weekend. A cold front is currently timing its arrival for Saturday, which will likely bring more widespread rain and a noticeable drop in temperatures. For now, keep your umbrella handy just in case that afternoon cap breaks, and enjoy the unseasonably warm March air.